Analytical performance and diagnostic accuracy of six different faecal calprotectin assays in inflammatory bowel disease

Abstract

Background: We evaluated the analytical performance of six different faecal calprotectin immunoassays together with their diagnostic accuracy in the discrimination between functional and organic bowel disorders. Methods: The faecal samples were obtained from inflammatory bowel disease patients (n = 27) at the time of diagnosis [Crohn's disease (n = 15), colitis ulcerosa (n = 12)], gastroenterologic disease control patients (n = 52) and rheumatologic disease control patients (n = 26). All individuals included in the study underwent a concurrent ileocolonoscopy. Analytical performance (imprecision, accuracy, carry-over, correlation and agreement) and diagnostic accuracy (sensitivity, specificity, likelihood ratios) of the different assays were evaluated. Results: All methods demonstrated good analytical performance, but within-run and total imprecision varied depending on the assay methodology used. Using Passing Bablok and Bland-Altman analyses, low quantitative agreement was observed between the assays. All assays showed excellent diagnostic accuracy, with areas under the receiver operating characteristic curves (ROC) ranging from 0.974 to 0.998. The AUCs were not significantly different between assays (p > 0.05). Diagnostic sensitivity at the

Faecal calprotectin to detect inflammatory bowel disease: a systematic review and exploratory meta-analysis of test accuracy

“…Two studies24 25 compared five and six different test assays at a common threshold of 50 µg/g. This allows for a test comparison in the same study population under similar study conditions.…”

“…Four assays (PhiCal, EK-CAL, Quantum-Blue and EliA) with five or more studies each could be considered in the comparison (online supplementary 8 for 2×2 data). Nineteen studies contributed data 10 24–41. Five studies10 25 31 39 40 contributed data to two different assays.…”

Development and Validation of a Test to Monitor Endoscopic Activity in Patients With Crohn’s Disease Based on Serum Levels of Proteins

“…41 Third, one of the major limitations of FC is the variability across platforms, collection techniques, and timing of sample collection, which have downstream implications on the diagnostic performance of FC. 22,26,[42][43][44][45][46][47] The EHI was built to ensure reproducibility and consistency in performance, which was observed throughout the validation process. Although no power analysis was performed for the comparison of the EHI and FC, we note that the sample size for this comparison was somewhat limited, with 247 samples in validation cohort 1 and 81 samples in validation cohort 2.…”

From bench to bedside: Fecal calprotectin in inflammatory bowel diseases clinical setting

“…Oyaert et al[ 17 ] compared six automated immunoassays: Thermo Fisher EliA Calprotectin assay on the Phadia 250 (Thermo Fisher Scientific, Uppsala, Sweden), Diasorin Calprotectin assay on the Liaison (Diasorin S.P.A., Saluggia, Italy), Inova QUANTA Flash Calprotectin (research use only) on the Inova BIO-FLASH instrument (Inova Diagnostics, San Diego, CA, United States), Bühlmann fCAL Turbo (Bühlmann Laboratories AG, Schönenbuch, Switzerland) on the Roche Cobas c501 (Roche Diagnostics, Mannheim, Germany), Euroimmun Calprotectin assay (Euroimmun; Lübeck, Germany), on an automated ELISA instrument (QUANTA-Lyser 2, Inova) and Orgentec Calprotectin assay on the Alegria (Orgentec Diagnostika, Mainz, Germany). The authors found that all assays had a sensitivity of 100% when the cut-off of the manufacturer was used ( i.e ., 50 μg/g), while the specificity at the same cut-off value ranged from 58.4% to 78.5%.…”